The Diet That Could Cut Your Cholesterol by 30%

There are several diets known to support heart health, including the Mediterranean diet, the DASH diet and the increasingly popular Blue Zones diet. Now, the Portfolio diet is gaining attention as one of the most effective eating patterns for lowering cholesterol.

A study published in Circulation analysed the diet data of 166,270 women and 43,970 men who had no cardiovascular disease at the time of enrolment in the mid-1980s and early 1990s. Participants completed food questionnaires every four years. After up to 30 years of follow-up, those with the highest adherence to the Portfolio diet had a 14% lower risk of heart disease and stroke compared to those with the lowest adherence.

So, what is the Portfolio diet? And how exactly does it help manage cholesterol? Here, experts break down what you need to know about this heart-smart eating plan and how to get started.

What is the Portfolio diet?

The Portfolio diet is a plant-based eating approach specifically designed to help reduce LDL or “bad” cholesterol—one of the major contributors to cardiovascular disease, explains cardiologist Dr David Sagbir. “This way of eating focuses on certain foods that have been clinically linked to supporting healthy cholesterol levels,” he says.

The diet is structured around four key food “portfolios”, and individuals can choose to incorporate one or more of them for cholesterol-lowering benefits, says dietitian Dr Melissa Prest.

What foods are in the Portfolio diet?

The Portfolio diet is low in saturated fat and dietary cholesterol. It centres on a combination—or “portfolio”—of four key cholesterol-lowering foods and nutrients, explains sports nutrition consultant Marie Spano. According to Dr Prest, a gradual approach works best: start with one of the core food groups and add the others over time.

The four core food “portfolios” include:

• Plant-based proteins such as soy, tofu and legumes
• Viscous (soluble) fibre from foods like oats, barley, berries, apples and citrus
• Nuts and seeds, which are rich in heart-healthy unsaturated fats, notes cardiologist Dr Alexander Postalian
• Phytosterols, which help reduce cholesterol absorption, typically found in fortified foods like yoghurt or taken as supplements

The eating pattern also features plant-based monounsaturated fats such as avocado and healthy oils, Spano adds.

While the diet doesn’t require you to completely cut out any specific food group, the focus is on limiting items high in saturated fat and added sugar, and instead prioritising nutrient-dense whole foods, says Dr Sagbir. “The good news is there are plenty of tasty options that align with this approach—some might even surprise you,” he says. Avocados, for example, tick multiple boxes: they contain monounsaturated fat, soluble fibre and phytosterols.

How does the Portfolio diet lower cholesterol?

The diet works by emphasising foods that contain nutrients proven to reduce LDL or “bad” cholesterol, says Dr Sagbir. “By including more of these foods in your day-to-day meals, you naturally crowd out less beneficial choices, creating a diet that supports heart health,” he explains.

The science backs this up. Studies show soy, nuts, plant sterols and fibre each play a unique role in managing cholesterol, says registered dietitian Keri Gans. “Soluble fibre binds to cholesterol and helps flush it from the body, plant sterols reduce cholesterol absorption in the gut, and replacing saturated fats with plant-based proteins and monounsaturated fats lowers the risk of heart disease,” she says.

Each of the four food groups in the Portfolio diet can reduce cholesterol by 5–10%, Prest notes. “That means if your diet regularly includes all four, you could potentially lower your cholesterol by up to 30%.”

Is the Portfolio diet actually good for heart health?

In short, yes. Research shows the Portfolio diet can significantly improve heart health. Studies have found that following this eating plan can lower LDL (or “bad”) cholesterol, as well as other established cardiovascular risk factors, says Gans.

“The Portfolio diet encourages heart-friendly foods and discourages those known to contribute to heart disease, like animal fats and refined carbohydrates,” adds Dr Postalian. While some of its features may sound new, it actually shares a lot in common with tried-and-tested approaches like the Mediterranean and DASH diets.

According to Dr Prest, three major studies have now shown the Portfolio diet is consistently associated with reduced risk of heart disease, reinforcing its benefits for long-term heart health.

Is there anyone who should avoid the Portfolio diet?

Generally, this plant-forward eating style suits most people, says Prest. That said, if you have a tree nut allergy, you’ll want to substitute nuts with seeds such as sunflower or pumpkin to maintain nutritional value without the risk.

Because this diet includes higher-fibre, higher-carbohydrate foods, people managing their blood sugar should take a balanced approach. Prest recommends pairing carbohydrate-rich items like whole grains and fruits with lower-carb plant proteins, nuts and plenty of non-starchy vegetables.

If you have inflammatory bowel conditions such as Crohn’s disease or ulcerative colitis, it’s best to speak with your gastroenterologist before starting, advises Gans. Likewise, if your current diet is low in fibre, introduce these foods gradually to allow your body to adjust.

Those with a rare condition called sitosterolaemia—which affects how the body processes plant sterols—should avoid this diet altogether, says Spano, as it could increase their risk of atherosclerosis (plaque build-up in the arteries).

If you’re recovering from or currently managing disordered eating, strict dietary changes may not be appropriate. Always check with your GP or dietitian before making significant changes to your eating habits.

The bottom line

Thinking about trying the Portfolio diet? Good news—it doesn’t have to be all or nothing. “Start with the easiest portfolio for you to adopt,” Dr Prest suggests. “Make small, strategic swaps and build from there.”

The diet doesn’t need to be fully vegetarian or vegan to be effective, adds Gans. The more consistently you incorporate these cholesterol-lowering foods, the more likely you are to see benefits.

And remember, your heart health isn’t just about what’s on your plate. As Dr Postalian puts it, “Don’t forget regular physical activity—it’s a key part of any long-term healthy lifestyle.”